IBEC Seminar: Valentin Nägerl
Monday, March 3 @ 12:00 pm–1:00 pm
Mind the Gap: Super-Resolution Imaging of the Extracellular Space of the Brain
Valentin Nägerl, Institut für Anatomie und Zellbiologie, Universitätsmedizin Göttingen Georg-August-Universität
Progress in microscopy has a long history of triggering major advances in neuroscience. STED microscopy, famous for shattering the diffraction barrier of light microscopy, is a case in point. It gives access to anatomical designs and dynamics of nano-structures, which are impossible to resolve using conventional light microscopy, from the elaborate anatomy of neurons and glial cells, to the organelles and molecules inside of them. Brain cells such as neurons and astrocytes exhibit an extremely elaborate morphology, and their functional specializations like synapses and glial processes often fall below the resolution limit of conventional light microscopy. This is a huge obstacle for neurobiologists because the nanoarchitecture critically shapes fundamental functions like synaptic transmission and Ca2+ signaling. Overcoming this problem, STED offers the chance to visualize the structural and molecular organization of brain cells in a living and dynamic tissue context, unlike traditional methods like electron microscopy or atomic force microscopy.
In the first part of my talk, I will review our contributions to developing live-cell STED approaches and their application to interesting problems in cellular neurobiology concerning the structure and function of neuronal synapses, and their interactions with glial partners. I will then introduce the topic of the extracellular space (ECS), which is increasingly attracting the attention of neuroscientists after yielding to novel labeling and imaging approaches. I will lay out the case for “shadow imaging” to visualize the convoluted physical structure of the ECS and, by implication, the dense and comprehensive microanatomical organization of living brain tissue. I will show published and recent data, illustrating the potential of the inverse labeling strategy for unbiased imaging of brain microstructure and dynamics in a panoramic and multi-scale way.
